View Full Version : Fuel Injectors and ECU


sylencce
07-07-2005, 11:21 AM
So if I put larger fuel injectors into my 04 WRX, say the STI injectors...will I have to remap the ECU for the bigger injectors or will they work and give me more power, just not as much if it was tuned???

Wingless Wonder
07-07-2005, 07:44 PM
Swapping STi injectors into a WRX with the stock turbo yields no gains. Even when the stock turbo is tuned for higher boost on 93 octane, the factory injectors have enough reserve flow capacity to accomodate it. The factory turbo is not efficient at much more than 16 psi. Go much beyond that and the turbo will heat the incoming air so much that it negates the increase in boost. A larger intercooler is just a band-aid fix at that point. The VF30, VF34, and VF22, are true bolt-ons that are much more efficient at making power for street-driven cars. Race turbos are another topic.

Look at the common parts that make up many tuner upgrade packages:

STi 'pink' injectors
Walbro fuel pump
VF30 or VF34 IHI turbo upgrade
EcuTek-tuned reflash
catless uppipe
turbo back exhaust system

If you had the time and the money, you might be able to find another turbo package that makes better power over a wide RPM range but these pieces are used by many tuners because it works well and can be had for reasonable prices.

--
0==WW==0
"…axles of evil…" - george w. bush

scorp88
07-07-2005, 07:51 PM
What about VF39+pinks? Or just VF39 no pinks?

Wingless Wonder
07-07-2005, 10:07 PM
VF39 and STi pinks should work out on a WRX but I don't know anyone personally that has done this. Many WRX owners still go with the VF30 or VF34 even though I see STi owners trying to sell off their VF39 when they upgrade to a bigger turbo.

You haven't filled out the Location field in your Member Profile. Do you have a local tuner in your area that specializes in Subaru?

--
0==WW==0
"…axles of evil…" - george w. bush

sylencce
07-08-2005, 07:32 AM
Wingless,

Thanks for the heads up. That's a big help and saves me some money. On a different not, which do you prefer on an ECU upgrade for a novice / begginner?

Cobb Accessport or a TurboXS Ecutek? I know you can do more with the Ecutek, but the Cobb is a safer bet as far as not blowing anything up. I know if I go with the Ecutek and have a local shop tune it, it's going to cost me out the YANG, but it will be done right and I'll most likely have a better tuned car...any thoughts or opinions on this are greatly appreciated...I just can't decide what to do...

and in case you're wondering my list of mods are

GReddy Evo2 Exhaust
Perrin Light Weight Crank Pulley
AEM Short Ram
Cobb Short Throw
Eibach Springs
Yoko AVS ES 100's (225/55/WR16's)

Next step hopefully this month is a helix up and down pipe upgrade

Again, any help is greatly appreciated.